The long term goal of this work is to identify and characterize the proteins induced by the interferons (IFNs) in normal and malignant cells, to determine if the biochemistry of IFN action is the same or different in normal and malignant cells, and to determine which of the IFN-induced proteins are key for the antiproliferative and/or antiviral effects of IFN. Having already identified by molecular weight and isoelectric point those peptides induced by the IFNs in normal cells, time course studies will be performed to determine the order in which peptides induced by the IFNs appear and to determine the duration of exposure to IFN necessary to induce their synthesis. The subcellular location of peptides induced by the IFNs will be determined. If any are secreted by normal or malignant cells, their role in the antiproliferative and/or antiviral effects of the IFNs will be determined. Using the PDQUEST system, computer based densitometric analysis of the autoradiograms of 2D gels will be employed to determine if there is synergistic induction of certain polypeptides by IFN-alpha and IFN-gamma in A 549 cells (carcinoma of the lung); by IFN-alpha and tamoxifen in MCF-7 cells (carcinoma of the breast); by IFN-gamma and TNF in Me 180 cells (carcinoma of the cervix); and by IL-1 and TNF in A 375 cells (melanoma). Finally, the NH2-terminal sequences of key IFN-induced peptides isolated from multiple analytical or preparative 2D gels will be determined. Our recent discovery that the IFNs induce polypeptides that are also induced by other cytokines suggests that there are common biochemical pathways for these biological response modifiers. Thus, these studies will not only increase our knowledge of the mechanism of actions of IFN but also of other cytokines as well.